John Raoux, Associated Press
Republican presidential candidate former Pennslyvania Sen. Rick Santorum, speaks to delegates before a straw poll during a Florida Republican Party Presidency 5 Convention Saturday, Sept. 24, 2011, in Orlando, Fla.

With Republican presidential contender Rick Santorum's surprise showing in three states last week, people are again talking about a "brokered convention." What exactly is that, and how could it happen?

Before the days of television and primaries, political parties chose their candidates at conventions to which delegates came as free agents, either uncommitted or empowered to change their minds once they got there. With multiple candidates in the running, the first ballot often did not produce a majority for any one of them, so that meant multiple ballots. If not enough votes shifted to produce a majority winner fairly quickly, those who controlled various blocs of votes — "power brokers" — stepped in.

Meeting in "smoked filled rooms" (cigars, not fireplaces) these men would either manage a shift towards one of the existing candidates — Abraham Lincoln, for example, in 1860 — or manufacture a whole new candidacy for someone who had not previously received any votes. That was a "brokered convention," one in which the decision is made as result of actions by power brokers on the ground, working through the delegates present, rather than primary voters and caucus goers who chose those delegates.

There could be a version of a brokered convention this time if four of the current Republican candidates stay in all the way and hold something close to their present positions. Simply as an illustration, project a first ballot with Mitt Romney at 35 percent, Rick Santorum at 30 percent, Newt Gingrich at 20 percent and Ron Paul at 15 percent. If every delegate stayed firm on subsequent ballots, there would be ballot after ballot and still no winner.

This is the dream of both the media, who would love the story, and those Republicans who don't like any of the current contenders. They see the possibility of a completely new candidate emerging — Chris Christie, Mitch Daniels, Condi Rice, Donald Trump, whoever. It would be a spectacle like no other, and the imagination runs wild.

It is not likely to happen. Paul will probably stay, because he doesn't really care whether he wins or not, but the others face some big primaries in which a good deal of money and organizational muscle will be required. We have seen how fickle the siren song of temporary momentum can be. When it stops singing for a candidate, no matter how he may have risen, his candidacy collapses — just ask Rick Perry.

Another reason it is unlikely is that it would virtually insure the re-election of Barack Obama, something that no Republican delegate would want. The Republican image is already slipping, as a result of the Congress where Republicans hold power in the House of Representatives, which has the lowest approval rating in memory. A divided, quarrelsome convention with multiple ballots would produce a battered nominee who would have to spend precious time healing internal wounds before he could turn his attention to the task of defeating a united, well prepared incumbent. That would damage the Republican image even more and hurt every Republican who shared the ballot with that nominee.

However, perhaps the strongest reason that there won't be a brokered convention is that there are no brokers any more. The days of political bosses who could control their state delegations with a word are long gone. If the Republican "establishment" exists to the degree that the media insists that it does, a single nominee would have been crowned already, and the remaining primaries wouldn't matter.

A brokered convention truly would be high drama. Those dreaming about it assume that it would produce the nominee of those dreams, who would soar on to triumph over Obama. It is not likely to happen.

Robert Bennett, former U.S. Senator from Utah, is a part-time teacher, researcher and lecturer at the University of Utah's Hinckley Institute of Politics.